1. Field of the Invention
The present invention relates to a fusion-type thermal transfer printing system for realizing multi-gradation printing with the use of at least one hot-melt ink.
2. Description of the Prior Art
When multi-gradation printing is effected with the use of a heat fusible ink, in general, a dither method of using a plurality of pixels (matrix) or a heat concentration method of using a special thermal head with small heating elements have been so far adopted.
In the conventional fusion-type thermal transfer printing systems, however, there exist problems in that in the case of the method of using a plurality of pixels, the resolution is deteriorated and therefore the image quality is degraded markedly; and in the case of the method of using the special thermal head, the cost of the printing system is inevitably high.